The best example of this of course is earth-moon-earth propagation.. If you point a high gain antenna at the moon, you will hear yourself about 2 seconds later on the echo return (The moon is approximately 250,000 miles away from the earth, and radio waves travel at 186,282 miles per second. A signal sent to the moon does not return until 2.7 seconds have elapsed), Doppler and phase shifted from the trip.. Pretty cool.
Oh, and you need about 1500 watts of power to overcome path loss... Try finding that in the YDI amp catalog. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Todd Boyle Sent: Friday, September 20, 2002 10:12 AM To: Tim Pozar Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: [BAWUG] goofball comments about reflectors At 09:36 AM 9/20/2002, Tim Pozar wrote: ... http://www.qsl.net/n9zia/pics/passive_repeater.jpg The diagram illustrates two reflectors in series. It seems to me, two reflectors set at precisely 90 degrees perpendicular would reflect any given signal back to its source, (the same as how bicycle reflectors work...) For example, if the City of Seattle put two reflectors on the Space Needle, any tenant, in any highrise could point a parabolic antenna at this reflector the reflected beam would paint all the windows on their side of their own building. And, all the *far* sides of all buildings along the line of sight...hmmm. Another application of reflectors: if A) you have some arbitrary hilltop or rooftop where one reflector could be installed and B) you have any number N of nodes you need to connect, it seems to me, you *might* be able to set the reflector to serve more than one path very nicely. perhaps many paths. Well, I guess this depends on how much power is lost in each bounce... TOdd At 09:36 AM 9/20/2002, Tim Pozar wrote: >Yup... They are known as passive reflectors or billboard reflectors. >Microflect specializes in this form of passive reflector. > >You can see an example of one at: > > http://www.qsl.net/n9zia/pics/passive_repeater.jpg > >Tim > > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED]]On Behalf Of Daniel Curry > > Sent: Tuesday, September 17, 2002 22:33 > > To: Jeremy Brown; [EMAIL PROTECTED] > > Subject: RE: [BAWUG] using metal wall as antenna > > > > Not an antenna, but maybe a reflector? > > > > -----Original Message----- > > From: Jeremy Brown [mailto:[EMAIL PROTECTED]] > > Sent: Tuesday, September 17, 2002 8:43 AM > > To: [EMAIL PROTECTED] > > Subject: [BAWUG] using metal wall as antenna > > > > Strange building problem. One of the rooms in our temporary office space > > apparently used to be a commercial kitchen. The shared walls are covered in > > stainless steel. > > > > Has anyone tried to use a large piece of metal for an antenna, apart from > > the radiation patterns not being uniform? > > > > Thanks, > > Jeremy > >-- >general wireless list, a bawug thing <http://www.bawug.org/> >[un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
